1. Technical Field
The present invention relates generally to image projection systems, and more particularly to a system and associated methodology for providing automatic shading of sensed overbright portions of an image projected by an LCLV projector.
2. Discussion
Light amplification-based video projectors driven by video signals should ideally produce uniform light patterns. However, due to inherent variations in system parameters, such as light valve film thicknesses, these projectors often produce light patterns with associated nonuniformities. The nonuniformities are amplified by projector amplifiers before the resultant image is output through a projector lens. The amplified nonuniformities produce undesired light and dark areas in images projected by monochrome projectors, as well as undesirable colored or overbright areas in images projected by multi-channel projectors.
The conventional approach to correcting image nonuniformities involves manually adjusting the brightness of the projected images through shading controls associated with the projector. Projection controls associated with the projector are often difficult for an inexperienced operator to use. Even with an experienced operator, images projected from such a projector often exhibit shading errors as a result of the subjectivity introduced by the operator, as the operator must rely on his or her eyesight in adjusting the projector to correct the errors. As a result, not only does such a process require a long time to execute, but the resulting projected images have less than optimal shading characteristics.